BoilerFaultCodes GM013 High
Boiler Fault Code GM013
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code GM013 appears across 1 boiler brand and 1 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.
Most common meaning Your boiler has detected an external signal telling it to shut down, which is often caused by an issue with an external control like a timer or a thermostat. (As reported on Baxi 400 Combi 2)
Pick your boiler brand for the GM013 fix
Source
Information for the GM013 fault code is sourced from the official service / installation manual for each model that displays it. Read more about how we source fault codes →
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026